Rough Idle Troubleshooting

[MoraleHazard]

This seems like a great forum. If some people can verify some observations for me, I would appreciate it. I have a 2001 X Sport w/ 68k mi. and have been noticing the following:

On a cold start (esp. on these frigid days), it idles a 1000-2000 rpms for about 30 seconds and then wants to die. If I manually keep the rpms up, it will soon idle at 900-1000 w/out dieing but it will run very rough. Sometimes, until the engine warms up it will "surge" somewhat with the RPMs going anywhere from 500 to 1200 or so, esp. w/ the truck in gear but stopped. I also had the check engine light come on. I took the x to autozone and they did the diagnostic. The light came on as "too lean". So I put injector cleaner into the tank. From searching, the forums it seems like the following could be problems:

IAC
MAF ?? Don't think so from what I read
Vacuum hoses
O2 Sensor.

Any advice, ideas, etc.?

Thanks.

 

[aldive]

Take a look at http://www.explorerforum.com/forums/showthread.php?t=169335&highlight=quest

 

[NHale623]

What were the codes that were pulled? Is your CEL still on?

 

[MoraleHazard]

The CEL showed up as "too lean" and that's it. The guy cleared it and it hasn't come back on.

 

[410Fortune]

too lean is not a code, anytrime you get the codes pulled ask for the actual digits P0174 or similar

Sounds like a vacuum issue to me

Does your 01 sport have the SOHC engine?

 

[MoraleHazard]

Rgr on the codes. Yes it's the SOHC.

Also, which is the best maintenance manual for the 01 Sport? IIRC, the Sport is the "new explorer" which was only the sport and sport trac in 01.

Where should I look for solving vacuum issues and would it be smart to continue driving the car if I don't solve the problem?

Thanks again.

 

[410Fortune]

I know what a 2001 Sport is, basically its a Gen II Explorer with a sport trac front clip, no biggie, underneath it is the same as any 97-2001 Explorer with a SOHC V6

Cleaning the MAS is never a bad idea
Cleaning your IAC is not a bad idea either, then re-set the computer (disco battery)

There are many ways to check for vacuum leaks or intake leaks, the best place to start is with a thurough visual inspection

I like the Chiltons manual far more then the Haynes, but both leave alot to be desired. The ford shop manual would be the way to go, or get the chiltons CD
and this website.

Try searching these forums for all this stuff

the SOHC V6 is known for leaking intake o rings, you can try a search for these as well

68K miles is about due for spark plugs, fuel filter, and more just FYI

 

[Patton]

My '01 x sport idles at 500-700 RPMs, is this too low? It also surges every once in a while, often the surge rattles the whole car.